Speed-indicating system.



M. R. HUTCHISON. SPEED I NDIOATING SYSTEM. AVPPLIOATION mum HEM. 17,1909.

Patented Jan. 2%, 1911.

4 sums-sum 1.

mmnon.

' WITNESSES:

. R. HUTCHISON.

SPEED INDIGATING SYSTEM.

APPLICATION FILED SEPT. 17, 1909.

Patented Jan. 24, 1911;

4 SHEETS-SHEET 2 M. R. HUTGHISON.

SPEED INDIGATING EYSTEM, ,APPLIOATIOH FILED SEPT. 17,1909.

Patented 52m. 2; 1911.

4 SHEETS-SHBBT 3.

mvErJmn M. R. HUTCHISON, SPEED INDIGATING SYSTEM. APPLIQAIIOH 'rILnn um.11, 1909.

Patented Jam24L19'1i1.

4 SHEETS-511E121 4.

WITNESSES:

INVENTOR employment 01 a multiple station system wherein independentunits each comprising ctr-an snares ra niar @FFECE KILLER REESEHUTCHISON, 0F SUMMIT, NEW JERSEY.

SPEED-INDICATING SYSTEM.

Specification of Letters Patent.

Application filed September 17, 1909. Serial. No. 518,198.

24th, 1908, as to which this application may be considered as in part acontinuation.

The present nvention also contemplates separate wiring for separategenerators and indicators, are used for each indicatin star tion, asdescribed in said prior application.

It also includes a system of primary and secondary units whereby thegenerators may be multiplied conveniently by mere addition of suchsecondary units without unnecessary duplication of the auxiliary partswhich. when once supplied with the primary E the right for revolutionsahead to deflecgeneralor units. may be utilized for all secondarygenerator units. I

This invention also includes various improvements which I have found tobe c.\'- trcmely important in the actual practice-of the invention undcrworking conditions.

My present system is particularly adapted for use on shipboard, andcontemplates the employment of a oomph-1c indicating system for eachpropcllcl' shaft of the ship. as well as a separate indicator for eachstation and preferably two energizing generators;

for each indicator. together with independcnt circuitconnections fromeach pair of gei'ieralors to the indicator controlled thereby. Thus. itthe ship has [our prtmellrrs,

and it is desired to indicate at three stalions revolutions of eachshaitahcad and aslcrn. as. for instance. in the engine roonu on thebridge. and at the wheel, there. are four indicators, one for eachshal't. at each station. and there are preferablytwo gcncr--ators-lorea'ch such indicator. thus making three pairs of generators oneach sha'l't.

'lhe particularform of generator selected torillustration herein issubstantially that indicated in Figures 3, 4. and 3 oi the above ap')hcation. iusomuch as the generators are induction generators adaptedto give voltage 'ariations varying in approximate proportion tovariation ot speed of the inductor shaft throughout the range of speedsto be indicated.

The indicators are preferably pro ided with central zero scales and withseparate coils adapted to be separately energized by conjoint action ofthe separate voltages from a pair of generators. in such manner 7 thatthe pointer will be deflected on one side of zero r speeds in onedirection and 1 the other side of zero for speeds in the re verse. Theindicators are separately calidn-atud to give theitrue revolut ons perminute value of propeller shaft rotation.

its is fully explained in my priorappln cation the actuation of themeasuring 1nstrum'ent. depends upon the phase relations of twogenerators constituting a PHJLFQDG .of said generators being arrangedfor slip of 90 degrees when the rection of rotation Patented Jan.24,1911. v

is reversed, thereby changing the phase of the voltage generated therein180 vdegrees, this reversal of phase relations causing the deflectionof'the indicator to reverse its direction, as. for instance, fromdeflections to cause there are no sliding or abutting contacts allconnections are soldercd,'and the design of themagneto is such that thepermancnt magnets, properly made and aged. have a practically closedmagnetic circuit at. all tinu-s. in the measuring instrument thearmature springs bringing the indicator hack to new have but slightstrains imposed and are very long;

in my system, momentary variations of shaft speed. such as would resultin uncertain vilirat'ion of the pointer, may be averaged and smoothedout..to any extent desircd. y apparatus for averaging such variationsof'speed so as to produce an aci curate steady rate indicatiom is prefe'ably f mechanical and consists of a spring drive or coupling introducedsomewhere between the propeller shaft and the generator shaft,

whereby, in a. given length at time, the

spring.

wheel between the spring and the generator,

which serves to maintain the speed of the generator shaft when thepropeller shaft naomentarily slows down, and to hold down the speed ofthe generator when the driver momentarily speeds up. By varying thespring. and fly wheel the indications may be made either to follow thespeed variations quite closel or to average them for a num-' ber'of-revoutions. v r

My 'invention'also includes an improvement in connection with the phaseshifting generator, which obviates a possible source .of error oruncertainty in the indications.

' L This difficult arises from the fact that the rotor is a re ativelylight-inductor or magnetic shield,-rotating' 1n the space=between thepoles of the permanent field and a cantrail-stationary armature, whichis energised by cyclic'distortion and shortcircuiting of themagnetic-field.- by the inductor. In this type of machine, the workdone. by the drive s aft is very'irregularly distributed,-ginso- -muchas the portion'of rotation where the inductor is approaching the pole isassisted by magnetic attraction of that pole, whereas the movement ofthe inductor away from the pole is resisted. Hence, with a lightinductor having a slip connection to the drive shaft,- the inductortends-to jump forward through a small are at a speed greater than thespeed of the drive shaft, whenever said inductor, is approaching-a pole.The'physical evidence of this is a chattering of the slip connectionof-the rotorto t e driv'e shaft and theelectrical result is adisturbance in the uniformit of the voltage generation and also a slig tinstantaneous shift-.' ing of the phase relations, both of which tend toimpair the steadiness and the Preliability 'of the indications. Theabove describeddifliculty may be overcome by addition oi any expedientfor op osing this polar acceleration movement 0' the inductor,

I a convenient embodiment of which-expedient consists in a relativelysmall balance 1 wheel rigidlysecured'to the inductor shaft. The energystoring capacity ofhis, balancewheel; should be such that theacceleration eifort'upon the inductor when; ap "reaching a pole will beabsorbed and resist At. the same time, the energy storingca-pacity ofthe balance wheel should not be as compared with the total work done inthe ner ator, for otherwise the speed eithe inductor will hotfall ofifast enough in case of rapid decrease in velocity of the drive shaft, as

when the propeller is stopped or reversed.-

. In the practical installation of a system,

such as above described, the convenient grouping of the pairs ofgenerators with respectio a single drive shaft controlled by an'-equalizer coupling between it and the pro- 3 peller shaft and also thegrouping .of the pairs wlth respect to each other are of considerablepractical importance. According to my invention,I provide a singleequalizer and propeller shaft connection with the primary set which alsocomprises at least one generator, controlling one indicator for'onestation, and then if indicators are re u1red ,for other'stations, Iarrange additiona generators or pairs of generatorssymmetricallydisposed'about the same. shaft and gear, or

on a shaftadapted to be alined and 'coupled to'said shaft, or I mayutilize both these ex'pedients, as in the preferred form selected 3 forillustration herein. I p

Each indicator has its own pair of n1ag netos. These pairs are groupedin;generat-.

ing sets, four magnetos to each primary unit,

and four or two-to each extension .unit, de-

pending on the number of, indicators desired.v It is, therefore,evident. that the shootin ers. This is important on warship systems.

Animportant feature of this system is the employment o f'magnetoscapable of generating only very minute current and low voltage, justsuflicient to operate thehigh resistaway or otherwise 'dama g any oneindicator doesnot afiect any 0 the othance'indicator's. Therefore,opening the circuit produces only a very faint, cool spark, and shortcircuiting causes substantially no obvious. The magnetos'are so designedand wound that continued short circuiting causes no injury whatever tothem;

The indicators are properly waterproofed' according to-navalrequirements: a f

The periodicity of the indicator pointer is so much less than thatv ofthe shi that heating of conductors; The advantage is Y pitching does.not affect it. If the in icator is placed with its scale in a planeextending fore and aft,'the pointer'will be substan tially unaffected byrollin 'of the ship. The

- movable coil and pointer eing mounted on 1 round jeweled ivots in theusual manner successfully resist mechanical jar, and are properly dampedtoj-make "tlIe5-instrument practically dead-beat. I

As stated, each indicatorhasits generating pair. The fixed indicatorsare permanent y connected thereto,.but anynumherofoutlets can heprovided" for; a portable I indi-.-

cator. ,If two portable indicators-avenues sapy,two generating pairsmust'beprovided, and due'attention paid to the fact that each indicatoris calibrated quits own generating. set. Owing 'tothe absence off'flotating parts other than easiii oiled ;.parts; "with no 0011- tacts toclean and all designed to give continued service over long intervals. noatten tion is necessary.

"In the accompanying drawings. Fig. 1 is a vertical sectionlongitudinally of the drive. shaft-of a practical form of generatoroutfit suitable for. coi'nniercial installations: Fig. 2 is an endcievation with one-half of the apparatus broken away in verticaltransverse Fig. 4 is a detail diagram of a pair of generators and theircircuit connections to an indicator controlled thereby;Fig. 5 is asimilar view showing the shifting of relations of, parts whenthedirection of rotation is reversed; ti and 'Lare diagrams of {thephase relations under the conditions illustrated in Figs. 4 and 5respectively. I

B'y reference to Figs. 1, 2, and 3, it will be seen that the generatoroutfit is spccili': cally adapted for a multiple station system whereindisturbance or accident, such as shorr-circniting or open circuiting. inthe circuit of any onestation cannot interfere tion of the outfitincludes a drive shaft, 21'

positive transmission mechanism bctwccn it and tl'ie propellcr shaftwhereby the total number of revolutions of the common shaft 40 must beara fixed ratio to the total number of revolutions of the propeller shaftand yet the ratio at any one instant may be greater or less so as topermit fluctuation of speed of the propeller shaft to be averaged to adesired extent on the drive shaft. in the specific. outfit selected forillustration. the system is one in which a pair of gcneratois isrequired for each indicator: but it will be. obvious that the samephysical disposition and mechanical arrangement of parts 'may beusefully employed for anyoutfit where a number of generators are to beused, irrespective of whether a single generator, or a plurality ofgenerators, are used in conncction with the several indicators, or

whether used for the production of the indications at a single stationor at several stations. v

Functionally considered. the primary unit consists of the mechanicalmeans for deriving suitably proportioned and averaged rotation from thepropeller shaft and includes parts to the right of the line X-X. Fig. l.this portion of the outfit being marliedA. 55 This part of the outfitincludes a bastcomsection on the line X -X, Fig.1; Fig. 3: is an endelevation from the leftv of Fig. 1,- the protecting casebeing shown insection 5 anism comprises a loose sprocket gear 9 engaging anantifriction noiseless Morse sprocket chain 10, driven by a suitable001- so lar gear 11 on propeller shaft 12. The sprocketgear 9 has anintegral hub or sleeve 13, to which are secured by pins 14. 14oppositely coiled spiral springs. 15. 16. secured at. their outer endsto pin 17 on fly wheel 18, which is formed with an overhanging rim' 19,which serves as a housing to protect such with respect to the shaft ts.

8 by key 35.

springs. The fly wheel 18 is fixed to'the shaft 8 by a key '20. Otherpins, one of which is shown at 21 in Fig. l of the drawings, may heprovided for securing'the coil springs under difl'erent degreesoftension.

In order to limit the extent to which the shaft '8 and tl \'"whccl l Smay lag behind or, lead the pulley 9,1110 sleeve 13 of the latter hassecured thereto a radially projecting lug 22, extended into the circulariath oftravel of;the' pin 17 and substantia ly (liametricallyoppositithereto. This limits both the lead amt lag of lly wheel 18 to ahalf revolution.

'lhc generators could be added by separate extension units to the abovedescribed parts. such as shown at but insomuch as at least. onegenerator is always used, I prefer to combine with the primary unit.onc'or more generators. in the outfit shown. generators 2-30 and3l arearranged as a pair bolted to the bed-'32. formed-on standard 1. similarpair 40, 41. may be arranged symmetrically with respect to saidpair30,31. and In this way provision is made for driving foungeneratorstroma single gca r 34. secured to shaft The gear connections of thegenerator 40 are the same as those ofgencrator 30. and those ofgenerator 41 are the same as those of generator 31'. except that 40andl'l arc inverted. (lcncrators3l-and 4-1 are driven through gears 38.39, rigidly secured to the inductor shafts thereof. and generators30.4.0 are driven through similar gears 42. respectively, whichare'mounted loosely on the inductor shafts, and drive the latter throughthe medium of-laterally projecting concentric lugs 44. 45, engaging lugs46. 47. which are rigidly secured 'to the inductor shaft."' Theperipheral-spacing of. the projections 44,45, apd'lugs 46.47, is soproportioned to permit slip through 90 9 25 from the shaft 8, whichalready has theredegrees. when the shaft is reversed. ,The small balancewheel 49, proportioned as hereinbefore described, and ri'gidly securedto the inductor shaft prevents chattering of the slip coupling.

Lubrication is provided for by means of grease cup 50, dischar 'ng'through a suit- "able channel 51, within sprocket gear 9.

The above described mechanism is prefer-.

- ably inclosed by a protecting case The endofthe shaft 8 is extendedbeyond the bearing 7 to afford means for coupling on any desired numberof extension generator units. Such a unit C is practically a duplicateof the mechanism abovedescribed,

with the positive drive and spring coupling omitted, because theextension unit is driven quired proportioned and averaged rate ofrotation with respect to the propeller. The

- extension unit is arranged with its drive shaftin line with the shaft8 and longitw dinally interlocked therewith, as at 58. "The outer end 68of the shaft 57, projects beyond its bearmgso as toafford means for con;

pling on' an additional extension unit, which may be siniilar to itselfin all respects.

It will be obvious from the above that all 'themagnetos are driven atthe same speed,

which is aspeed directly roportional to the speed of the shaft 8, anthat the speed of the shaft 8 is properly' averaged for variations ofthe propeller shaft by the spring coupling, while its total number ofrevolutions per unit time always bears a fixed ratio to the total numberof revolutions of the propeller'shaft, and also that the ratio of thegearing is such that the slowest contemplated rotation of the propellershaft 12 will drivethe generator shafts at a speed sulficient togenerate ari appreciable voltage sufficient to give definite variationson the'in- .dicator.

In Figs. 4, .5, 6, and 7, I have shown the physical and electricalrelations of the two generators constituting'a pair, both with respectto each .other and with respect to the reactive part 'sof the.indicator. Figs. 4 and 6 illustrate these. conditions when thepropeller shaft is driven in one direction, while Figs. 5-and 7illustrate the conditions when the propeller shaft is reversed.

The two magnetos 30, 31, have stationary armatures 92, 93,-respectively, and their rotary inductor-s94, 95 are bothdriven from thesame shaft 8. One of them, as at 31, has

its-inductor 95 rigidly keyed to its shaft,

while theother, as 30, is securedso as to slip clrcumferentially throughan angle of 90 dc.-

ees; In one directionof rotation the slip r of 94 brings it in exactshown in Figs. 4 and 6, w iereas rotation in the other direction,accompanied by circumferential .slip through an. angle of 90 do grees,changes the phase of the alternatin current produced thereby 180 degreeswit respect ,to the currentsgenerated in 92, as

two generators are applied through inde; pendent circuits to thestationary field coils and movable indicator coil respectively;

The operation isas follows: Whenthe generator shaft is rotated in adirection to hase with 95, as

shown in Figs. 5'and 7. The voltages of the, a

bring the generators in the same phase as shown in Fig. 4, the voltageap lied through lead 72 and terminal 73, to 0011 88, thence back throughterminal 74 and return- 7 5, to the other terminal of the generator. 31.

Currents inthe same phase from generator r 30 traverse lead 76to=terminal 77, therice through fieldcoils 86,. 87' to terminal 78,thence through return 79, back to generator 30. direction and phase thuscaused to traverse the field and indicator coils cause 'deflectionof-the index. 90.iri a direction indicated in "Fig. 4, as toward theright. When the enerator shaftreverses andgth'e indepen ent currentsbecomeofopposite phase byslip of inductor 94, as shown inFig. 5',thecurrent from 31 through the indicator coil, is the same as before,butthe current from 30 is The independent'currents in the same reversedwith respect thereto, so that when the alternation causes flow ofcurrent from 31 out through 7 2, an equal current from 30, instead offlowing out through 76.and back through 79, flows out thrbugh'79'and'back through 76,. thus-causing the index 90 to move to the left. asindicated in Fig. 5.

shaft alloy is a very simple matter, the support being provided by theforeand-aft .bulkhead. The large sprocketis' previously made to conformto the shaft diameter, and

g Installing the generating units in the the smaller sprocketproportioned to shaft I diameter and maximum speed of rotation.

Calibration is done aboard ship, after the indicators are installed andconnected to their generators by separate circuits run through separateconduits. The large.

sprocket which is to be attached to the propeller shaft is attached to amotor driven dummyshaft, and the generator sets, mounted permanently inposition, are chain driven therefrom. To the dummy shaft is geared astandardized tachometer. Temporary telephonic connection is madebetweenthe calibrator and each of the men stationed at the indicators. Thespeed of the dummy shaft is gradually accelerated and as thestandardized tachometer readings are phoned to the indicator. men, thescale subdivisions are made by a special marking tool mounted on abridge over dia-l. These are then filled in properly and the calibrationis done. As

each instrument is-calihrated inits position 3 as Well as on-its owngenerators, all factors which might interfere with perfect accuracy ofthe indications are compensated for by g the calibration. The largesprocket then transferred from the dunnny shaft to the propeller shaftat a point opposite the sprocket J and the chain it) is applied. The

revolution indication having been correctly indicated for the largesprocket, the indications will be correct when that sprocket istransferred to the propeller shaft.

\Vhile I have herein fully shown and described, and have pointed out inthe ap-' pendedclaims certain novel features of construction,arrangement, and operation which characterize'my invention, it will beunderstood by those skilled in the art that various omissions,substitutions, and changes in the forms, proportions, sizes, and detailsof the device and of its operation, may be made without departing frommy invention.

I claim:

1. The method 'of determining or indicating speedor rates of work of anapparatus both when driven forwardly-and when reversed, which comprisesgenerating :1 pl nrality of sets oi'alternating voltages or currentsproportional to the speed or rate of work of, such apparatus and in onephase re-.

lation when the apparatus is driven in one direction, and in anotherphase relation when the apparatus 13 driven in the other direction, andcompounding and measuring the voltages or currents of each set.

2. The method of determining or indicating speed or rates-of work of anapparatus both when driven forwardly and when reversed, which com risescontrollin the generation of a plum ity of sets of a ternating voltagesor currents in such manner as to cause. the same to vary proportionatelyto the speed or rate of work of the apparatus, compounding each set ofvoltages or currents in such a manner that the said voltages or currentsreact in phase when the apparatus isv driven in one direction, and outof phase when the apparatus is driven in the other direction, andmeasuring the compounded voltages or currents.

3. The method of determining or indicating speed or rates of work of anapparatus both when 'driven forward and when reversed, which oomprisesgenerating by induction a plurality of.sets of alternating voltages ofcurrents proportional to the speed or rate of work 0 such apparatus andin phase when the apparatus is driven in-one direction, and out; :ofphase whenthe apparatus is driven in the other direction, andcompounding and measuring tl voltages or currents of each set.

the generators for indicating speed in onedireetion when the generatorsare 111 one of said phase relations and in the other direction when thegenerators are in the other of said phase relations.

5. In a speed indicator, two induction generators, connections from onegenerator to the other whereby the two generators are caused to bedriven together 1n both directions, the setting of said connections withrespect to the generators being automatically changeable upon'thereversal of the drive to cause the generators to act in phase, or out ofphase, according to the direction of the drive, and means connected tothe generators for indicating speed in one direction whenthe generatorsare in phase and in the other direction when the generators are out ofphase.

6. In a speed indicator, two electrical generators,connections from onegenerator to the other whereby the two generators are caused to bedriven together in both directions, the setting of said connections withrespect to the generators being changeable uponthe reversal of the driveto cause the generators toact in one phase relation or in another phaserelation, according to the direction of the drive, and means connectedto the generators for indicating speed in one direction when thegenerators are in one of said phase relations and in theother direct-ionwhen the generators are in another of said phase relations.

7. In a speed indicator, two induction generators, connections from onegenerator to the other whereby the two generators are caused to bedriven togetherin both directions, the setting of .said connections withrespect to the generators being changeable upon reversal of the drive tocause the generators to act in phase, or out of phase, according to thedirection of the drive, and a meter having windings one of which isconnected to one generator and another of' which is connected to the0ther generator, said windings having relative, movement n one directionwhen the generators are in phase, and in another direction when thegenerators are out ofiphase.

8, In a :speed indicator, two induction generators, connections from onegenerator to the other whereby the two enerators are caused to be driventogether in both direcnone, the setting of said connections with eratorsto 'act in phase, or out of phase, .210-

I caused to be driven together in both directions, the setting of saidconnections with respect to the generators'being changeable i phase.

tions, said connections ermitting of a limators to act in phase whendriven in one diirectiomand out of phase when driven in the otherdirection when the generators are out of phase. i v

13. Ina speed indicator, two electrical generators, means for causingsaid generection' and out jot phase when driven mthe according to thedirection of the drive, and 'a'volt meter connected to ,the generatorsfor indicating speed in one direction when the generators are in phaseand in the other 5 direction when the generators are in phase atom areout of. phase.

generators, means for causing said generdirection and-out of phase whendriven in the other direction and to shift from one phase setting to'theother phase setting when the direction of the drive is changed, and

means connected to the generators for indichanged, and ineanZQ connectedto the'gener- 'ators for indicating speed of drive in one respect to theenerato'rs being changeable upon reversal '0' the drive to causethegencording to the direction of the drive, and a volt meter having afield winding connected to one of said generators, and an indicatorwinding connected to the other-of said generators.,

'9 In ,a speed indicator, two induction generators, "connections fromone generator to the other whereby the .two generators are upon there'versal of the drive to cause the generators to act in phase, orout ofphase,

tion when the generators area'out of 10. In a. speed indicator, twoinduction generators, connections from one generator ,to the otherwhereby the two generators are caused to be driven together' nbothdirecited angular shift or ,8 ip" of one generator with'respeet to theother rupon reversal of the drive to cause the generators to act inphase,- according to the dilQCiIlOILOf the drive, and'means connected tothe generators for indicating speed in oneand inthe other direction whenthe gener 11. In a speed indicator, two electrical ators to act in phasewhen driven in one eating speed of drive in one direction when thegeneratorsare in phase, and for indicating'speed of drive in the otherdirection when the generators are out of phase.

12. In a speed indicator, two electrical generators, meansior'causingsaid generother direction and automatically toshiftfrom onephase setting to the other phase setting when the direction of the driveisdirection when the generators are in phase, and for ind cating ,speedof drive. in, the

ators to act inphase when driven in one diother direction, and to shiftfrom one phase I setting to the other phase settin when the direction ofthe drive is change and indicating means controlled by connections fromsaid generators, and havingtwo scales and a device movable relativelthereto toindicat on one scale the rates 0 drive in one direc tion andon the other scalethe rates of drive in the other direction, accordingto the phase relation of the generators.

14. In an apparatus of the class described, a movable device thespeedand direction of movement of which isto be.determined, a

pair of alternating current generators having permanent magnetic fieldsand stationaryarmaturewindings, in combination with means connecting thegenerators with said movable device for driving the generators at speedscorresponding to the speeds of said movable device, and means comprisingseparate circuits from'said generators compounded in a single indicatingdevice-for -utilizing the voltages of said generators to.

tionary armature windings, and rotating inductors, 'incombination withmeans connectingthe-generators with said movable device for driving thegenerators at speeds "corresponding to "the speeds of said movabledevice, and means comprising separate circuits from said generatorscompounded in a sin-' gle indicating device for utilizing the voltagesof said generators to produce proportional indications of thevspeeds ofthe movable device, and'to indicate'thedirection of motion of themovabledevice. 4

16. In an apparatus of the class described, a movable device the speedand direction of inoveinent'of which is to be determined, a

pair of alternating current generators, each generator beingproportioned and arranged to generate voltages approximatelyropor-ttional to speeds of'its shaft thron iout a considerable range of speedsof saidshaft, multiplying driving i connections between saidmovable-device-and said generators, the

ratio of multiplication being predetermined.

with respect to the speeds of the drivin member and-tothe speeds ofproportiona variations of voltages of. the-generators, so that thenormal rangeof speeds of said driving member will drive the generatorsat speeds lying within the-limits of said proportional variation ofvoltage, together with means comprising separate'circuits from saidenerators compounded in a single in- 'dicating"d evice -for utilizingthe voltages of said generators to produce proportional indications ofthe speeds of said movable-device and to indicate the direction of itsmotion.

17. A multiple station speed indicator, comprising a central generatingstation consisting of a plurality of generators, a pro portional speedshaft. and multiple gearing connecting said generators with saidproportional speed shaft to drive all the generators at the same speed.in aanl.pination with a shaft whose speed is to'ffe measured'and towhich said central generating stationis adjacent, positive multiplyingdriving and speed-averaging connections between said last named shaftand. said proportional speed shaft, and a plurality of speed indicatinginstruments in circuit with the central station.

18. A multiple station speed indicating system comprising an indicator,circuit c011- niections, and a generator for. each station,

'all said generators being located at a cenured, intermediate powerconnections for tral station, and means for'positivelydrivmg saidgenerators at the samespeed, said driving means comprising a commonmultiplying and variation-averaging power connection to the shaft whosespeed is to be. measured. 4'

19. In a multiple generator speed ndicating system, a proportional'speed shaft adjacent the shaft whose speed is to be measdriving saidproportional speed shaft and for averaging thereon the momentaryvariations of the drive shaft, incombination with a plurality ofalternating current generators, driving means between said proportionalspeed shaft; and said generators whereby said generators are driven atthe same speed in a predetermined phase relation by said proportionalspeed shaft, and speed indicating "means connected to said generatorsand actuated therefrom.

20..ln a multiple generator speed indicating system, an indicatingdevice,a proportional speed shaft adjacent the shaft for driving saidproportional speed shaft and for averaging thereon the momentary.

variations of the drive shaft, in combination with a plurality ofalternatin current generators arranged above ant below said shaft. meansfor driving said generators "at the same speed from said shaft, andspeed indicating means connected to said generator and actuatedtherefrom.

22. in a multiple generator speed indicating system. a proportionalspeed shaft. adjacent the shaft Whose speed is to be measured,intermediate power connections for driving --sai(l proportional speedshaft and for averaging thereon the momentary variations of the driveshaft. in coml'iination with a plurality of alternating currentgenerators ar ranged in. pairs, means for driving said generators at thesame speed from said proportional speed shaft, and speed indicatingmeans connected to said generators and actuated therefrom,

23. A multiple generator speed indicating system, comprising aproportional speedshaft ad acent the shaft whose speed is to bemeasured, intermediate power connections for driving said proportionalspeed shaft and for averaging thereon the mo mentary variations of thedrive shaft, a plurality of alternating current generators arranged inpairs, at single gear wheel mounted on said proportional speed shaft,drivin connections from said gear to each of sai 24. A speed indicatingsystem comprising a pair of alternating current generators, means fordriving them at the same angular speed in either direction of rotationso as to generate voltages in phase when the generators are rotated inone direction, said driving means having a slip member to permit ofangular slip of one generator with respect to the other upon reversal ofthe drive and having means for limiting such slip, whereby the phaserelation of said generators is nged one hundred and eighty degrees whenthe drive is reversed, an energy absorbing means for controlling theaction of said slip 'member. and .speed, indicating means connected tosaid generators and actuated therefrom.

25.. In a speed indicating system depending for its operation on theshift of phase- -relations of alternating currents, two alternatingcurrent generators, one of said generators comprising a stationarypermanent magnetic field, a stationary armature, and a rotary inductorhaving a slip connection with its drive shaft, whereby reversal of theshaft causes slip of one generator with respect to the other throughanangular distance corresponding to a half cycl of'the alternatingcurrent, in combination with energy absorbing means adapted to absorb anamount. of energy-large as compared with the momentary accelerationefforts on the I v s pairs of generators, and speed indicating meansconnected to said generators and actu' ated therefrom inductor and small-as'comparedwith the total work done by-the inductor, and speedindicatin meanseonnected to said generators an act ated therefrom.

' speed indicating system dependoperation on the shift of phase astationary armature, and 'h-avinga. slip connection e shaft, wherebyreversal of the imi't'd slip of one generator pg spending to a alfcyc eof .the alternatrng'current, in combination 'with {a flyiyyheel'proportioned to have an ener y athing capacity large as compared with te momentary acceleration efi'orts onthe inducat "fc i'i" and small ascompared with the total Twork done by the inductor, and speed indicatingmeans connected .to said generators v and actuated therefrom. v

' 27. "In a multiple-generatorspeed indicatz'llte'rnating currents, twoilltepfl'i generators,.one of said gen-. g-a stationary permanent let-tto the'other through an an ularing systemfa primary comprising a ;2proportional speed shaft adjacent the shaft whose speed is to bemeasured, an intermediate power connection for dr vmg said proportionalspeed'shaft from sald SeCOIld named shaft and for averaging thereon the3' momentary 'variations of the drive shaft in .second sliaft, 'andspee' indicating means connected to said generators andactuatedtherefrom, a I

- 'Signed' at New York cit- ,in the county and-State of New York, this15th day of September, A. D. 1909. p

I LE REESE HUTOHISON.

Witne sses.:'.

I GEORGE C. DEAN, v

IRVING Onnmorrr.

